Methods of Coupling of Photosensors to Microcontrollers

The paper deals with the methods of coupling photosensors with microcontrollers.a The urgency of the work is due to the need to find ways to reduce the spread of the COVID-19. One of methods consists in place ultraviolet lamps in crowded places, such as subways, hospitals, as an effective method of counteracting the spread of a COVID-19. Because the dose of ultraviolet radiation is also potentially dangerous in the case of a long-term stay near the source of ultraviolet, the development of a detector of ultraviolet radiation is a very important task. The development of a ultraviolet detector involves the analysis and selection of a sensor (primary converter) and a secondary converter. Analog-to-digital converter or microcontroller can be used like secondary converter. In work are considered different photo detectors like photoresistors, photodiodes and phototransistors. The technical characteristics of photoresistors, photodiodes and phototransistors are presented in order to select the primary optical transducer for further construction of the ultraviolet radiation detector. As a result of the analysis, it is proposed to use photodiodes as the primary converter, because it has high sensitivity and speed, as well as low cost. For use in the ultraviolet detector, it is necessary to select diodes that are sensitive to ultraviolet radiation. For this task, must be used wide-gap semiconductors. It is proposed to take ultraviolet sensitive semiconductor structures based on thin films of A2B6 materials, due to the fact that these structures are manufactured and researched at the National Academy of Sciences of Ukraine and have technical characteristics at the level of foreign analogues. As secondary converters it is suggested to use microcontrollers, which have a number of advantages such as: the small area that the microcontroller occupies on the board, flexibility of electronic circuit setup, multifunctionality, increased performance, high accuracy and speed of calculations. In the article given describes how to connect the primary converters to the microcontroller. For some photosensors in the work proposes the approach of constructing an ultraviolet detector without a separate amplifier, using only microcontrollers. Also in article are briefly presented analyze of different microcontrollers, such as PIC, AVR, ARM, their technical characteristics, principles of work. The main attention is paid to methods of coupling microcontrollers with optical sensors on the example of a photodiode.